On Thu, May 28, 2009 at 22:19, Stroller <strol...@stellar.eclipse.co.uk> wrote: > What's the difference between supporting the "certain set of instructions" > with "-march=" and doing so with USEs? > > Or doesn't "-march=" support additional "certain sets of instructions". What > does it do, then?
The difference is that with the USE flag, you enable the use of assembly code in the source of mplayer that makes use of the "certain set of instructions". The -march option enables the use of the "certain set of instructions" when gcc is optimizing and so gcc will use the "certain set of instructions" when it converts the source code into assembly code. Ward
